Derivation of formula for orbital ranges in hydrogen atom

AI Thread Summary
The discussion focuses on deriving the formula for orbital ranges in a hydrogen atom using angular momentum quantization and centripetal force equations. It establishes that the angular momentum is quantized as integer multiples of h-bar and relates centripetal force to the attractive Coulomb force between the electron and proton. The derived formula for radius shows a decrease with increasing quantum number n, indicating a potential error in reasoning. The author invites others to identify the mistake, suggesting that the correct relationship may involve the reciprocal of the derived equation. Clarification is offered that linear momentum is distinct from angular momentum in this context.
jjr
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I almost have the answer, I'm sure there's just a minor flaw in my reasoning. Here it goes:
We're given that the angular momentum of the atom is integer multiples of h-bar (n\hbar) (integer depending on the orbit). Now the centripetal force is given by F = \frac{mv^2}{r} = \frac{p^2}{mr} = n^2\hbar^2/mr where m is the electron mass, v is the velocity, p is the angular momentum and r is the range. This force equals the attractive coloumb force between the proton and electron, so: \frac{p^2}{mr} = \frac{k(q^2)}{r^2} => r = k(q^2)m/(n^2\hbar^2) where k is coulombs constant, q is the charge of electron/proton.

The problem is obvious, seeing as how the radius drops with higher n's. The answer is in fact the reciprocal of the right part of the last equation. Can anyone spot my error?

Thanks, J
 
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Bump. If something is confusing, I'll be happy to elaborate
 
p=mv is linear momentum, not angular momentum.
 
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